Variable speed transmission



w. Nom/KA 23,03%881 VARIABLE SPEED TRANSMISSION Filed MIOh`l8, 1933 3Sheets-Sheet l q TTORNEYS pri 7 1936.

April 7 1936, W NOWKA VARIABLE SPEED TRANSMISSION Filed March 18, 1933 5Sheets-Sheet 2 muuu WITNESS:

VARIABLE SPEED TRANSMISSION Filed MaIOh 18, 1933 5 Sheets-Sheet 3Lig-.lf

WITNESS! ATTQRNEYS' tid NITED STATES .t iiLE SPEED TRANSBIISSIN WernerNowka, Pawtucket, R. ll., assigner, by

mesne r l lyn, N.

ents, to Paul Kollsman, rook- Appiicauan Maren it. mit, serial No.conico 'l iUlaiins.

This invention relates to improvements in power transmissions and moreparticularly to variable speed transmissions.

lThe primary object of the invention resides in a mechanical powertransmission having an infinite variation of speed from zero up to, and,if and when desired, even beyond the speed oi a drive shaft rotating ata constant speed.`

"While the basic principle involved in this invention is variableeccentricity as disclosed in my rio-pending application for LettersPatent, Serial No. 439,987, filed March 29, 1931i, it has now beenpossible to so far transcend the scope of the iormer invention, thatcertain radically new',l basic principles have been established, as willappear from the following:

First, it becomes possible to employ an eccentric mounted on a driveshaft to rotate a driven member directly connected thereto, and thuseliminate Aall intermediate motion transmitting elements,

andsecondly, these new principles oder construction possibilities,wherein the fluctuation due to gyratory or oscillating motion of thedriving eccentric can be equalized.

With these and other objects in view, the invention resides in. thenovel construction, combi-s nation, and arrangement of parts, theessential features of which are more fully described in the specication,are iully set forth in the appended claims, and are illustrated in theaccompanying drawings, in which:

Figure l is a vertical longitudinal sectional view of the invention.

Figure 2 is a vertical transverse sectional view on the line l--l ofFigure l.

Figure 3 is a detail perspective view oi the eccentric drive shaft.

.Figure i is a vertical transverse sectional view on the line filt oiFigure l.

Figure 5 is a horizontal sectional view on the line t-t oi Figure d. i

Figure 6 is a vertical transverse sectional view on the line t-'t oiFigure l.

Figures i and d are diagraatic cross seoS tional views showing thesimplest torna oi' the principle oi the invention.,

Figure a is a detail cliagr' ratio view illusm trating the 4undcrlyingprinciple of the rau'ven design tor the adjustment oi nuctuation.

Figure lil is a detail vertical sectional view illustrating one iorm oibalancing the eccentric showing the parts in neutral position. v

Figure ll is e. vertical transverse sectional view on the line lllii oiFigure ld.

(lOl. 'ld-lill Figure l2 is a view sar to Fie ll showm ing the parts ineccentric position.

Figure 13 is a detail vertical sectional view through a modiiication orbalancing the eccentric showing the parts in neutral position.

o Figure it is a view similar to Figure lt, but

showing the parts in eccentric position.

Figure 15 isA a vertical transverse sectional View on the line ltrlt olFigure 13.

For the salte of clearness, it is believed il the principle oi theinvention is best seen in Figures 'i and 8 of the drawings, and adescrip-a tion' oi this'simpleform will be proceeded with at this `time.Referring to these ngures, the numeral l designates a ring of annularcasing while tting against the inner periphery ol the ring are spacedsegmental shaped inclined plane members, l, la, and 2b. The bases of themembers rest against the inner side oi the r and the rise of the samedoes not exceed the i: of repose, that is, any tendency oi the inclinedplane or wedge members to slide baclrward along the ring under anypressure exerted upon the inclined surface, must be completely absorbedby the angle of friction between these surfaces. in the presentinstance, three inclined surfaces are shown but any desirable number maybe provided that will produce the desired result hereinafter explained.

Rollers t, tu, and tb, respectively,- enge the inclined faces of themembers l, lo, and il, d are held thereagainst by another surface whichis in the form oi" an eccentric il lixedly, mounted on a roller driveshait. The eccentric d constitutes a rotatable driving element which retbecomes smaller, a corresponding pressure is en i erted upon the rollersto, and tb, and the latter are adapted to successively roll down alongthe respective inclined planes a distance corresponding to the rise oithe eccentric.

For example, the roller in Figure l during a duartcr revolution oi theeccentric has rolled down the inclined plane i from the lull lineposition to the advanced position shown in dotted lines, or a distanceequivalent to the angular displacement between the langles oi theinclined plane and that oi the eccentric.

it is obvious that the angular displacement 'above referred to would begreater' with 'an in creased, and smallerwith a decrmsed eccentricity,and therefore, ii the eccentricity becomes mdable, the distance offorward travel of the roller becomes correspondingly variable. Thisprinciple could be directly employed to drive a shaft to be driven bytransmitting the power from the rollers to such shaft, however, if butone roller and inclined plane were employed, only an intermittent motionwould be transmitted to a driven shaft as the eccentric will riseagainst that plane only during one half revolution of the same,

hence the use of two or more rollers and inclined i planes as shown.With such an arrangement, one roller is always being rotated forward,whereby a continuous forward rotation is obtained.

Each of the rollers are connected to one end of expansion springs 5, theopposite ends being connected to the hind end of the wedge member of thefollowing roller, thus a spring 5 extends from the roller 3 to planemember 2a, another from roller 3a to plane member 2b, etc.

From the foregoing description taken in conjunction with the full anddotted line positions of the parts shown in Figure 7, it will be seenthat during a quarter revolution of the eccentric, the same has not onlyrotated roller 3 forward, but has also released and become separatedfrom roller 3a. However, the spring 5 between roller 3 and wedge member2a has immediately expanded accordingly, and with the roller 3 drivingfrom behind, has forced roller 3a forward, keeping it in contact withthe surface of the eccentric 4 which is now in position to rotate theroller 3a forward the very instant it releases the roller 3. The rollers3a and 3b correspondingly operate as the eccentric completes its fullrevolution.

Having thus obtained a continuous forward rotation by the successivemovement of the rollers, the same need only be connected to a shaft tobev driven in order to rotate that shaft continuously in a forwarddirection an angular distance corresponding to the driving eccentricity.This may be accomplished by various means such as aconventional form ofclutch arrangement, or a system of springs such as shown in Figure 8 ofthe drawings. In this construction the rollers 3, 3a and 3b extendbeyond the plane of one end of the eccentric 4 and wedge members and arerespectively disposed between the radially extending arms 6 carriedby adriven shaft '1. Expansion equalizing springs 8 are interposed betweenopposite sides of the rollers and the adjacent arms 6. Thus it will beseen that, as the rollers are successively moved during rotation of theeccentric 4, the same will impart a corresponding movement to the drivenshaft 'I through the rollers 3, 3a, and 3b and springs 8.

Having explained the general principle of the invention as illustratedin the diagrammatic views I and 8, a practical application of the sameembodying additional features is illustrated in Figures 1 to 6inclusive. The fundamental principles involved in the form issubstantially the same as above described, but the position of theinclined planes and the rollers are reversed, that is, instead of therollers rolling off the inclined planes, the latter roll off therollers. Thus power must be taken from the member having the inclinedplanes for transmission to the shaft to be driven, rather than from therollers as previously set forth. Briefly, the inclined plane in thisform is interposed between the driving eccentric and the roller, thelatter being held against an annulus.

In this construction, the numeral 5 designates a rotatable drive shafthaving one of its ends journaled in ball bearings I0 mounted in arectangular shaped housing section II. The drive shaft extends into thehousing section II and is formed with an eccentric socket I2, while theWall of the socket is provided with a slot I3, which extends inwardlyfrom the outer open end for a purpose to be presently explained. Fittinginto the eccentric socket I2 for turning movement therein is anauxiliary drive shaft I4 keyed to the socketed end of the main driveshaft 9 by a collar I5 slidably mounted on the socket end of the saiddrive shaft. The collar I5 is provided with a key lug I6 which extendsthrough the slot I3 into a spiral groove II formed in the auxiliaryshaft I4. The key lug and slot in addition to keying the auxiliary shaftwith the main shaft, also serves a purpose to be hereinafter explained.The outer end of the socket is journaled in an anti-friction bearing I8and projecting beyond the plane of the bearing and formed integral withthe auxiliary drive shaft I4 is an eccentric stub shaft I9, the axis ofwhich may be brought into. axial alinement with the drive shaft 9 or outof alinement therewith by the turning of the auxiliary shaft I4 relativethereto, whereby to change the eccentricity from zero upwardly. From thedescription thus far, it will be seen that if the eccentric stub shaftI9 is set in axial alinement with the axis of the shaft 9, as shown inthe drawings, the same will turn on the same axis as the drive shaft,but by setting the stub shaft I9 to a position eccentric to the driveshaft, the same will turn in and out with reference to the center ofrotation as the shaft I4 is turned about its own center within theeccentric socket I2.

Rotatably mounted upon the eccentric stub shaft I9 is a driven member 20in the form of a rotor having a series of inclined planes 2| on theperiphery thereof, the ends of the inclined planes terminating inoutwardly extending stop fingers 22. A roller bearing 23 is interposedbetween the eccentric shaft I9 and the driven member 20. Bolted orotherwise secured to opposite sides of the member 20 are disk plates 24and 25, the latter overlying the end of the eccentric shaft I9 andconstituting a coupling plate as will be hereinafter explained. 'I'heperiphery of the disk plates 24 and 25 extend beyond the periphery ofthe member 20 and are provided with outwardly extending lugs 26.

Enclosing' the member 20 and its co-related parts is a cylindricalcasing section 21 which is bolted to the casing section II and toanother casing section 28. The inner peripheral wall of the casingsection 21 is provided with a bearing ring 29 and between the bearingring and the respective inclined surfaces of the member 20, are rollers30. The rollers are of a Width approximating the width of the member 20and extending axially from opposite ends thereof are pintles 3|, whichare mounted in iioating bearings 32, which slide on the outer curvedsurfaces of the plates 24 and 25 between the stop lugs 26. Contractilesprings 33-have one of their ends connected to a lug 26 and their otherends to the floating bearings 32 to normally urge the rollers in onedirection and which permit of the relative sliding movement of therollers with respect to the member 20 and the plates 24 and 25. 'I'hesesprings act to always -hold the periphery of the rollers in bearingcontact withthe ring 29 and respective inclined planes 2| of the member20.

Extending into the housing section 28 in one end of a. driven shaft 34,the same being rotatably mounted in an anti-friction bearing 35.Although various types of flexible couplings may be til) amasar employedto connect the driven member 2li with the driven shaft 34, li haveillustrated a construction which will serve the purpose and whichconsists in providing a disk 36 on the inner end of the driven shaftagainst which a coupling plate il ts. The coupling plate is interposedbetween the disk 36 and plate 25 and is provided with two sets ofdiametrically opposed slots 38 and 39. Lugs dll extend from the disk 36into the slots 38 while similar lugs 4l extend into the slots 3% fromthe plate 25. The slots are of suilicient length to compensate for thegyratory action of the eccentrically driven member 2W during rotation ofthe member 2li when in driving operation. From the description thus farof the form shown in Figures l to 6 inclusive, the advantages thereofare apparent. For example, a system of inclined planes, shown in Figure7 independent of each other, are now combined into one single unit it,which not only simplies the construction as well as the operation of theunit, but eliminates all secondary driving elements such as clutches,springs, and the like, and thereby most important, this integral unit ofa system of inclined planes becomes itself a single driven memberdirectly rotated by the eccentric on which it is mounted by means of theanti-friction bearing 23. Further important advantages of this directlydriven member of the -greatest practical value can now be obtained.

First, both the roller 3l] and its coacting inclined plane rotatetogether, which means, that for any given angular motion of the drivingeccentric and any given eccentricity, the inclined plane during thecorresponding angular displacement rotates twice the distance that itsroller moves forward. This in turn allows of a considerably greaterforward movement of the driven member 2li at comparatively smalleccentricities, thus increasing the possible range of variation to apoint where by proper design of the respective angularity and length ofthe inclined planes composing the driven member 2U, a speed considerablyfaster than the drive speed of the eccentric can be obtained, theminimum speed, of course,v

remaining zero at zero eccentricity.

Secondly, and of equal importance from the standpoint of practicalapplication, the angularity between the respective inclined planes 2land bearing ring 29 constantly changes during the forward rotation ofeach inclined plane, and this fact, together with the above mentioneddouble motion. by which an inclined plane is being displaced against afulcrum (the roller) which itself rotates forward and therebypractically doubles the forward rotation of the plane during thedisplacement, has a pronounced tendency to materially reduce o-neicature, which always has been an objection against drives takingvariable eccentricity as a basis for variable speed, that, namely, ofthe iiuctuation in speed due to the harmonic motion of the eccentric.

This form of an integral driven member directly rotated by the eccentricwithout any inter-`Y vening elements consisting of a system of inclinedplanes does much more than merely tend to reduce the aforesaidobjectionable fluctuation, as it offers the possibility of actuallyovercoming or eliminating it entirely. It,will be seen that the drivenmember 2l) remains free to rotate forward ahead of the eccentric stubshaft l@ on which it is mounted, thus taking on the function of a flywheel and automatically smoothing out the speed iluctuations by reasonof the inertia developed. Furthermore, the curve of each of the inclinedplanes comprising the driven member 20 can be so designed, that the rateof displacement changes inversely with the rate of speed of the drivingforce. This point is best seen in Figure 9 of the drawings.

In Figure 9 the full lines indicate the neutral position of a singleinclined plane and its roller, as the pdsition of the eccentric shaftlll is shown at zero eccentricity, or in a position concentric with thedrive shaft. 'I'his position is thegneutral position for all operatingparts. For the sake of illustration, it is assumed that the roller 30when in the neutral position shown in full lines contacts the inclinedplane 2l at the center of the curve of that plane, and that the maximumspeed occurs at a time when the driving eccentric is in the positionshown in` dot and dash lines, that is, at the instant when the line offorce generated by the eccentric drive strikes the roller in its neutralposition on the curve of the plane. This is not actually true, as inreality the maximum speed occurs some fteen to twenty degrees ahead ofthe line of force, but the assumption is most convenient. for the sakeof simplicity in this illustration.

Given the angle A as the angle of repose between the outer ring 39 andthe inclined plane il, the center of the normal curve would be at thepoint B and the radius for said curve would be C. This normal curvewould now cause an even forward rotation for any given displacementeffected by an even driving speed, but would of course, also cause anincreased speed as the neutral point is being approached and a decreasedspeed after the neutral point has passed, whereever the driving speed,as is here the case, itself increases and decreases. But, if the radiusbe shortened as indicated at D as shown in dot and dash lines, the curveassumes the shape here shown in dotted lines E where the angularitytoward the neutral point increases, thus causing less displacement andthereby slower speed, and again this angularity decreases, thus causinggreater displacement and thereby faster speed after the neutral pointhas passed.

It is conceded that as the maximum speed occurs at slightly differentangles with different eccentricities, such a curve can be geometricallycorrect only for one given eccentricity, and therefore for all othereccentricities a slight fluctuation still remains at leasttheoretically, but it can be stated, nevertheless, that with thisprinciple, a curve for the inclined plane may be designed which leavesroom only for such an utterly small fluctuation, that for all practicalpurposes it can safely be neglected as entirely eliminated.

Aside from the fact that the driven member acts as a ily wheel, andfurther, that the curve of the inclined planes composing this ly wheeldriven member can be so adjusted that all fluctuation for'all practicalpurposes is already overcome, a further equalization of even the slightremaining theoretical fluctuation can be eifected by the proper designin connection with still another function cf the driven member Ell aswill be seen hereinafter.

While a smooth, continuous rotation of the driven member is nowobtained, the eccentric motion utilized for driving also causes agyrating movement inwardly and outwardly relative to its center ofrotation, as appears from the very nature of the operation.

In operation, as the drive shaft 9 rotates, assuming that the shaft i4has been adjusted to move the stub shaft I9 to eccentric position, andthe direction of rotation is as shown by the arrow in Figure 2 of thedrawings, the driven member 20 which is mounted on the eccentric stubshaft I9, is lifted or forced outwardly to` Ward the rollers 30, and theinclined planes 2I contacting with respective rollers are forced tosuccessively roll oif forward in their angular displacement; thusrotating the driven member 20. Only one roller operates at a time andduring which operation, the other rollers are in idling or releasedposition. It is for this reason that the springs 33 are provided as theyserve to ccntract the instant pressure on the respective rollers isreleased to force the rollers to remain at all times in contact withboth the outer ring 29 and the inclined planes 2I. Thus, each inclinedplane remains in operating contact with its corresponding lroller untilmaximum angular displacement due to the rise of the eccentric has beenreached, at which time the next inclined plane and roller automaticallybecomes operative. The action is therefore similar to a gear, in thatthe successive inclined planes corresponding in a way to gear teethsuccessively engage and release when in operation.

The rotation of the driven member 20 is gyratory but a continuousrotation is imparted therefrom to the driven shaft 34 through theflexible coupling consisting of the coupling plates 25, 36, and 3l. Theoperation of the exible coupling is somewhat similar to the principleinvolved in ordinary exible couplings but with this characteristicdifference, that the radial distance of the points where the load istaken on by the driven shaft, remains xed, the lugs 4i] being rigidlymounted on the driven shaft, and furthermore, the load is transferredfrom the gyrating lugs 4I in the same plane of action, both ses of lugsr*xtending ino the same coupling plate 3l. It is therefore evident thatnot only does this ceupling plate 3l adjust the gyrating movementproduced bv the cccentrically driven member 2U, but any tendency of oneof the lugs 4i to move faster or slower is prevented, since neither ofthe lugs 4U can move faster or slower than the oher, both beiner xed inthe same common carrior at equal distances from the center, and anyd'ierefnce in speed must tierefore be taken up in the coupling plate.

For the purpose of manually controlling the am( unt of eccentricity ofthe stub shaft I9, I provide the following. Journaled in the housing Ilis a rotatable stem or shaft 42, the outer end of which carries a handwheel 43 while the inner end has a gear 44 xed thereto. Also jcurnaledwithin the housing and disposed on opposite sides of the socket I2 ofthe drive shaft is a pair of shafts 45, the upper ends of which carrygears 4G, which are .in meshing engagement with the gear 44, Worms 4'Iare provided on `the shafts 45 intermediate their ends and which meshwith gears 48 on screw shafts 49, which are journaled within the housingand extend parallel to the exis of the drive sho ft. Threaded on thescrew shaft 49 are slide bl'cks 50, whichexiend into the groove I in thecollar C5. The slide blocks also extend into tracks or guide channels 52formed in the inner walls of the housing Il.

For obtaining an adjustment of the driving eccentric shaft I9 theoperator turns the hand wheel 43 which imparts rotation to the shafts 45through meshing gears 44 and 46, from where turning movement is impartedto the screw shafts 49 through worms 41 and gears 48, the

rotation of the screw shafts imparting a longitudinal feeding movementto the blocks 50, causing collar I5 to slide longitudinally along thesocket end I2 of the drive shaft. This sliding movement causes turningof the eccentric shaft I4 due to the key lug extending into the spiralslot lI of the shaft I4. This construction permits of a very accurateadjustment of the eccentric form neutral or zero eccentricity upwards.

From the foregoing description, it will be seen that when the stub shaftI9 is in a position, concentric with the drive shaft 9, there can be norotation of the driven member 20, but as this part is turned out fromthat center, it becomes the driving eccentric and rotates the drivenmember in a manner already described, from where the power istransferred to the driven shaft 34 through the flexible coupling. Thusthe driven shaft is rotated at an even velocity and cznstant flow ofpower at a speed controlled by the amount of eccentricity of theeccentric stub shaft I9.

In the construction of large size transmissions of the kind describedthe weight of the driven member 20 rotated by the eccentric I9 isgreatly increased, and when in addition, a larger eccentricity is used,the centrifugal force generated by its eccentric motion may set upvibrations detrimental to the unit. It is advisable, therefore, in suchcases to keep the eccentric I9 and the driven member 20 rotated therebyin balance at all times. One simple way of balancing the driven member:fs to connect a counter-weight to the driven m'rnber in any convenientlocation. One location is illustrated in Figures 10, 11, and l2, whereinthe driven member 25 is formed with an annular recess 53 which opensthrough one side of the driven member, the open side fitting against afixed plate or part of a housing I I Disposed within the recess 59 isthe counterweight consisting of two or more eccentric rings slidablymounted one within the other and designated at 54, 55 and 5Grespectively. In a concentric or neutral position as shown in Figuresand 11, the combined eccentric rings form a large concentric ring placedin the center of the recess 53 in such manner, that a clearance isprovided between the surfaces of the recess and the counter-weight ring,corresponding to the maximum eccentricity to be employed, and the weighto the combined rings 54, 55 and 5G corresponds to the weight of thedriven member 20, plus the eccentric stub shaft i9 with its rollerbearing 2li.

The inner eccentric ring 54 is provided with an annular flange on oneside which is received in an annular concentric groove 58 provided inthe closed side wall ofthe driven member 2B', while the outer eccentricring 5B is provided with an annular eccentric flange 59 at one sidewhich is received in a groove 6U provided in the plate or casing il andwhich is concentric to the center of rotation.

In operation of the counter-weight construction, as the stub shaft I9and driven member 20 move into an eccentric position as shown in Figure12, and the center of mass of the member 2D and stub shaft IS are movedout of the center of rotation equal to the distance marked X of theeccentricity, the inner eccentric ring 54 by virtue of its ange 5'!running in the groove 58, is pressed out in the same direction and tendsto take counter-weight along. The flange 59, however, radially xed inthe groove 80 in the casing, offers a resistance, and the individualeccentric acaaeai rings dit, b and lit are forced to slide off on eachother and adjust themselves in the position shown in Figure 12, wheretheir combined weight decreases in the direction of the eccentricmovement of the member 2li' and correspondingly increases in theopposite direction in the same proportion as the mass of the drivenmember 2t shifts its weight in the eccentric'direction, thus holding theeccentric in` balance, whatever the position of the stub shaft lil anddriven member ffl' may be.

Whilethe above described method of balancing the driven member fil iscomparatively simple, compact, and inexpensive, the pressure exerted toeffect the adjustment of the eccentric rings causes some efficiencyloss, even if rollers are interposed between the surfaces of the eccen-ltric rings to reduce friction. Where, therefore, it is desired tobalance the eccentric without efficiency losses, the modification shownin Figures 13, 14, and may be used, although a bit more expensive thanthe construction set forth in the preceding modification.

In this form the construction is similar to that shown in Figures l to 6and similar reference characters refer to like parts. In this form, theend plate f5 fixed to the eccentrically driven member E@ is hereprovided with an outer angular or beveled surface 6l. A counter weightt2 is disposed adjacent the beveled side of the plate and hascorresponding angular or beveled segmental shaped members tf slidablymounted therein, the angular or beveled surfaces of which face towardthe beveled surface t l. Radially disposed grooves ift and tt arerespectively arranged in the beveled surface tl and segmental shapedmembers dd and face each other to provide grooves or pockets forballs'tt which have bearing engagement on the bearing ring 2f.

In Figure 14, the parts are shown in eccentric position, wherein theplate fb fixed to the driven member fd has been forced out from thecenter of rotation in one direction and thereby drives a ball tt alongthe reaction surface fl! of the casing at right angles to the directionof the eccentric, and the ball in turn has forced the counterweight ftout of the center of rotation in the 'opposite direction by an amountcorresponding to the outward movement of the center of the mass of thestub shaft le plus the driven member 2t, thereby holding that mass inbalance.

While I have shown and describedwhat I consider to be the generalprinciple of my invention, I wish it to be understood that such changesin construction as come within the scope of the appended claims may beresorted to if desired.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent of the United States, is:

l. In a power transmission, a drive shaft, an eccentric mounted on saiddrive shaft, a driven member rotated by said eccentric, a reactionmember, and rotatable elements Vco-operating with said driven member andreaction member to cause rotation of said driven member and permitoverrunning thereof.

2. In a power transmission, a drive shaft, an eccentric mounted on saiddrive shaft, a driven member rotated by said eccentric, a reactionmember, a driven shaft, rotatable elements cooperating with said drivenmember and reaction member to cause rotation of said driven member andpermit overrunning thereof, and flexible coupling means to impartrotation from the driven member to the driven shaft.

3. In a power transmission, a drive shaft, an eccentric rotatable bysaid drive shaft, a reaction member, a driven member rotatably mountedon said eccentric embodying a series of angular surfaces, and rotatingelements engageable with said angular surfaces and co-operating withsaid eccentric and said reaction member to impart ro- 1gation from saiddrive shaft to said driven mem- 4. In a power transmission, a driveshaft, an eccentric mounted on said drive shaft, a driven member`rotated by said eccentric, a reaction member, rotatable elementsTcti-operating with said driven member and reaction member to causerotation of said driven member and permit cverrunning thereof, and meansfor changing the eccentricity of the said eccentric.

5. In a power transmission, a driving member, a member havingunidirectional angular surfaces, rollers engageable with said surfaces,a driven member co-operating with said rollers, and means operated bysaid driving member and adapted to approach and recede from said rollersto cause said rollers to rotate forwardly along said surfaces. Y

6. In a power transmission, a drive shaft, a driven shaft, a reactionmember, an eccentric mounted on said drive shaft, a flexible couplingdirectly mounted on said eccentric and operatively connected with saiddriven shaft, means embodied in said flexible coupling including aseries of angular surfaces and a series of rotating elementsrespectively engaging the angular 4 surfaces and interposed between saidangular surfaces and said reaction member for imparting rotation fromsaid drive shaft to said driven shaft.

7. In a power transmission, a drive shaft, a driven shaft, a reactionmember, an eccentric mounted on said drive shaft, a nexible couplingdirectly mounted on said eccentric and operatively connected with saiddriven shaft, means embodied in said flexible coupling including aseries of angular surfaces and a series of rotating elementsrespectively engaging the angular surfaces and interposed between saidangular 'surfaces and said reaction member for imparting rotation fromsaid drive shaft to said driven shaft, and. means for adjusting theeccentricity of said eccentric.

